In many instances, a dendritic migration can develop between two electrodes under a voltage differential. For example, a migratory species (e.g., silver) within one of the two electrodes can migrate in a dendritic pattern when moisture (e.g., in a non-hermetically sealed integrated circuit package, or an integrated circuit package having a compromised hermetic seal) and the voltage differential are present. The migration of the migratory species follows the direction of the field created by the voltage differential. The dendritic migration can, in time, bridge one electrode to the other electrode and cause a short circuit failure.
Occurrence of a dendritic migration requires, for example, a migratory species, a differential field, a migration surface, and a migration environment. In some instances, the migratory species can include silver (e.g., from the silver brazing used in joining electrodes). The differential field can include a voltage differential or other types of electromagnetic fields capable of providing a field force. The migration surface can be an even surface of a support substrate. The migration environment can include a moisture layer due to humidity condensation on a non-hermetic (e.g., not airtight) integrated circuit package.
Air cavities in non-hermetic semiconductor packages are prone to cause the aforementioned dendritic migration effects, which can eventually change the electrical characteristics of a device toward an eventual short circuit failure. Some known expensive solutions include: removing the migratory species from the electrodes, and/or flooding the air cavities with a substance that can reduce or remove the migration environment (e.g., reducing surface humidity).